In its latest quarterly "Threat Report" (released on 27 June 2018), cybersecurity firm McAfee found that the number of cryptojacking cases surged by 629% in the first quarter of 2018.

The term "cryptojacking" refers to malware infections that result in someone's computer (phone, tablet, laptop, desktop computer) running cryptocurrency mining software without the user's knowledge.

According to McAfee Labs, which is the Advanced Threat Research division of McAfee, it detected over 2.9 million cases of "coin miner malware" infections in Q1 2018 compared with almost 400,000 such cases in Q4 2017.

The report notes that

"This suggests that cybercriminals are
warming to the prospect of monetizing infections of user
systems without prompting victims to make payments,
as is the case with popular ransomware schemes.
Compared with well-established cybercrime activities
such as data theft and ransomware, cryptojacking
is simpler, more straightforward, and less risky. All
criminals must do is infect millions of systems and start
monetizing the attack by mining for cryptocurrencies on
victims’ systems. There are no middlemen, there are no
fraud schemes, and there are no victims who need to be
prompted to pay and who, potentially, may back up their
systems in advance and refuse to pay."

Commenting on the report, Raj Samani, who is Chief Scientist at McAfee, said:

"Bad actors demonstrated a remarkable level of technical agility and innovation in tools and tactics. Criminals continued to adopt cryptocurrency mining to easily monetize their criminal activity.”

“Cybercriminals will gravitate to criminal activity that maximizes their profit... In recent quarters we have seen a shift to ransomware from data-theft, as ransomware is a more efficient crime. With the rise in value of cryptocurrencies, the market forces are driving criminals to crypto-jacking and the theft of cryptocurrency. Cybercrime is a business, and market forces will continue to shape where adversaries focus their efforts.”